Method for displaying a relationship of a measurement in a medical image

ABSTRACT

The embodiments described herein relate to a method and system for simultaneously displaying relationships of measurements of features associated with a medical image. In one embodiment, a plurality of measurements of features associated with a medical image are provided. Each of the plurality of measurements corresponds to a respective measurement type. Relationships are created between the measurements and references specific to the measurement types, and at least two of the created relationships are simultaneously displayed in a graphical display format. Examples using fetal growth data and time intensity curves are disclosed. Other embodiments are provided, and each of the embodiments described herein can be used alone or in combination with one another.

RELATED APPLICATIONS

The present patent document is a divisional claiming priority toco-pending divisional U.S. Pat. No. ______ (Ser. No. 11/823,243, filedJun. 26, 2007) and co-pending divisional U.S. Pat. No. ______ (Ser. No.11/823,411, filed Jun. 26, 2007), which claim priority to parent U.S.Pat. No. 7,252,638 (Ser. No. 10/601,413, filed Jun. 23, 2003), issuedAug. 7, 2007, each of which is incorporated by reference.

BACKGROUND

Some of the objectives of an obstetric ultrasound examination are todetermine whether the growth of a fetus is consistent with a bestestimate of the fetus' age and to determine whether the relative sizesof various anatomical components are in correct proportion. To supportthese objectives, medical diagnostic ultrasound imaging systems candisplay fetal growth data in the form of “growth curves,” which depictthe expected size of a component of fetal anatomy as a function ofgestational age. FIG. 7 is an example of a conventional fetal growthcurve showing biparietal diameter (BPD) as a function of gestational age(GA) over the course of a gestation. As shown in FIG. 7, the growthcurve comprises three distinct plotted curves: one representing the meanor expected biparietal diameter for a given gestational age (curve 1),and two other curves above and below the mean showing the normalstatistical variation to be found among healthy fetuses (curves 2 and3). The growth curve also shows a data point (X), which is thebiparietal diameter measurement acquired during an ultrasoundexamination of a patient. A sonographer or physician makes adetermination regarding the status of the fetus by looking at the growthcurve to determine whether the measured anatomy lies within a normalrange.

Separate growth curves are generated for different types (or“dimensions”) of fetal growth data, and each of these growth curves areexamined to obtain a global picture of the normalcy of the fetus'growth. Because growth curves only show a single dimension of fetalgrowth data and current ultrasound systems and image review systems onlydisplay a single growth curve at any given time, a sonographer orphysician must page through a sequence of growth curves to diagnose thefetus' growth. This sequential analysis of growth curves introduces arisk of a missed diagnosis since a key growth curve can easily beoverlooked. Similar problems can occur with other measurements offeatures associated with a medical image.

SUMMARY

The present invention is defined by the following claims, and nothing inthis section should be taken as a limitation on those claims.

By way of introduction, the embodiments described herein relate to amethod and system for simultaneously displaying relationships ofmeasurements of features associated with a medical image. In oneembodiment, a plurality of measurements of features associated with amedical image are provided. Each of the plurality of measurementscorresponds to a respective measurement type. Relationships are createdbetween the measurements and references specific to the measurementtypes, and at least two of the created relationships are simultaneouslydisplayed in a graphical display format. Examples using fetal growthdata and time intensity curves are disclosed. Other embodiments areprovided, and each of the embodiments described herein can be used aloneor in combination with one another.

The embodiments will now be described with reference to the attacheddrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart of a method of an embodiment for simultaneouslydisplaying fetal growth data.

FIG. 2 is a block diagram of a medical diagnostic ultrasound imagingsystem of an embodiment.

FIG. 3 is an illustration of a graphical display format of anembodiment.

FIG. 4 is an illustration of a graphical display format of anotherembodiment.

FIG. 5 is an illustration of a graphical display format of anotherembodiment.

FIG. 6 is an illustration of a graphical display format of anotherembodiment.

FIG. 7 is an illustration of a prior art growth curve.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS Introduction

In general, the embodiments described below can be used tosimultaneously display relationships of measurements of featuresassociated with a medical image. In operation, a plurality ofmeasurements of features associated with a medical image are provided.Each of the plurality of measurements corresponds to a respectivemeasurement type. For each of the plurality of measurements, arelationship between the measurement and the reference specific to itsmeasurement type is created. Then, at least two of the createdrelationships are simultaneously displayed in a graphical displayformat.

A “measurement of a feature associated with a medical image” can be anyquantification of a physiological attribute that (a) appears directly ina medical image (e.g., the diameter of a heart chamber), (b) is acalculation derived from raw imaging data (e.g., a calculation ofResistance Index), or (c) is available through the imaging system eventhough it is not data that is used to create a medical image (e.g.,heart-rate made available to the imaging system via an EKG which plugsinto the imaging system). The following is a list of examples of variousmeasurements of features. This list is not comprehensive, and othermeasurements can be made, such as those listed athttp://www.echobyweb.com/htm_level2_eng/formulas&calculations.htm.

-   -   Tumor diameter/area/volume.    -   Various organ and organ component diameters/areas/volumes.    -   Blood flow velocity through various significant vessels, for        example, different sites on the Carotid Arteries, the Pulmonary        Vein, the Aorta, Hepatic vessels, renal arteries, blood vessels        in the legs.    -   Resistance index (RI) of blood flow through a vessel, where RI        is defined as |Vmax−Vmin|/max(|Vmax|, |Vmin|), where Vmax is the        systolic velocity and Vmin is the diastolic velocity measured        during a heart cycle.    -   Time-Averaged-Velocity (TAV) of blood flow through a vessel.        This is the average flow velocity over a set span of time.    -   Pulsitility index (PI) of blood flow through a vessel, where PI        is defined as |Vmax−Vmin|/TAMx, where Vmax is the systolic        velocity, Vmin is the minium diastolic velocity, and TAMx is the        maximum velocity averaged over (at least) one cardiac cycle.    -   Ratio of blood velocity at systole and diastole.    -   Vascular Stenosis, which is the percent blockage of a blood        vessel, calculated from measurements of the vessel's outer        diameter and inner diameter, or alternatively the outer        cross-sectional area and inner cross-sectional area.    -   Ejection Fraction, which is the proportion of blood pumped out        of the heart with each beat, computed from measuring the        percentage change in heart chamber volumes between systole and        diastole.    -   Wash-in and wash-out rates.

The measurements have normal ranges and ranges outside the norm, whichare indicative of some kind of pathology. Given that there is anexpected “normal” value (e.g., an average value found among a healthypopulation) and an expected standard deviation away from “normal” foundamong healthy persons, then any measurement can be expressed in aunitless (normalized) way by using the following equation:NormalizedMeasurementValue=(Measured Value−“Normal”Value)/StandardDeviation. The NormalizedMeasurementValue is then simplythe number of standard deviations away from “Normal.” Because anymeasurement can be normalized in this way, regardless of the measurement(whether it be a distance, a volume, a flow velocity, etc), it ispossible to meaningfully display diverse measurements on the same x-yplot, where the vertical (y) axis is the unitless measure of deviation(measured in standard deviations) from normal and where the horizontal(x) axis is the plurality of measurements of features associated with amedical image.

As discussed above, each of the plurality of measurements corresponds toa respective measurement type, and each of the plurality of measurementsis associated with a reference specific to its measurement type. If allof the measurements correspond to the same measurement type, all of themeasurements can be compared to the same reference. Otherwise, eachmeasurement can be normalized to an appropriate reference specific tothat measurement type. Then, all the normalized measurements can bedisplayed together to provide a meaningful comparison of the differentmeasurements relative to “normal.” This makes it possible tosimultaneously display measurements of diverse nature, for example, aheart rate (bpm), a flow velocity (m/s), and a wall thickness (mm). Eachof these is measured in different units, but they all have expectedranges (e.g., an average value for healthy patients, and a standarddeviation to be found among healthy patients). By normalizing eachmeasurement relative to its expected range (e.g., how many standarddeviations away from average is it?), all the measurements aresimultaneously displayable in a single plot. Simultaneously displayingthese relationships in a graphical display format can be used to assista user diagnose a healthy or unhealthy condition. Various types ofmeasurements can be simultaneously displayed, and the choice of whichtypes to simultaneously display can be made by a user.

The following examples illustrate the embodiments described above asapplied to fetal growth data and time intensity curves. It is importantto note that these embodiments can be used in other applications andthat the following claims should not be limited to fetal growth data ortime intensity curves unless explicitly recited therein.

Example Using Fetal Growth Data

One application of the general technique described above relates tofetal growth data and will be described in conjunction with the flowchart 100 of FIG. 1. As shown in FIG. 1, a medical diagnostic ultrasoundimage of a fetus is generated with a medical diagnostic ultrasoundimaging system (act 110), such as the medical diagnostic ultrasoundimaging system 200 illustrated in FIG. 2. As shown in FIG. 2, theultrasound system 200 comprises a transducer probe 205, a beamformer210, a processor 220, a display device 230, a storage device 240, and auser interface 250. Some or all of the functionality described hereincan be performed by the processor 220 running software (i.e.,computer-readable program code) stored in the storage device 240 or someother location not shown. Alternatively, some or all of thefunctionality described herein can be implemented purely with hardware(e.g., with the processor 220 alone and/or with other hardwarecomponent(s) not shown). The hardware/software components can take anysuitable form. Further, the ultrasound system 200 can compriseadditional components, which are not shown in FIG. 2 for simplicity. Forexample, although only a single processor 220 is shown in FIG. 2, itshould be understood that the ultrasound system 200 can comprisemultiple processors and that the functionality described herein can beperformed by a single processor or can be distributed among severalprocessors.

During an obstetrics ultrasound examination, a sonographer contacts thetransducer probe 205 with a patient, and the ultrasound system 200generates an ultrasound image of a fetus. In general, the ultrasoundsystem's processor 220 causes the beamformer 210 to apply a voltage tothe transducer 205 to cause it to vibrate and emit an ultrasonic beaminto the portion of the patient's body in contact with the transducer205. Ultrasonic energy reflected from the patient's body impinges on thetransducer 205, and the resulting voltages created by the transducer 205are received by the beamformer 210. The processor 220 processes thesensed voltages to create an ultrasound image and displays the image onthe display device 230. In addition to being displayed on the displaydevice 230, a generated ultrasound image can also be stored in digitalform in the storage device 240 for later review. Images can also betransferred to removable media (e.g., a magneto-optical disk) or sentover a network (e.g., a local area network in a hospital or theInternet).

Once the ultrasound image is displayed on the display device 230, thesonographer measures anatomical components shown in the displayedultrasound image using displayed measurement tools that are manipulatedwith the user interface 250 (act 120). Based on the measurements of theanatomical components, a plurality of fetal growth data is generated(act 130). As used herein, the term “fetal growth data” broadly refersto any data that is generated based on a measurement of an anatomicalcomponent shown in a medical image and that can be used to assess thegrowth of a fetus. As also used herein, fetal growth data is “based on”a measurement when the fetal growth data is the measurement itself or isthe result of a calculation using the measurement.

The following are some examples of fetal growth data. It should beunderstood that the term “fetal growth data” as used in the claims isnot limited to the following examples and that other forms of fetalgrowth data can be used. Information about these and other fetalbiometry measurements can be found at the following sources, each ofwhich is hereby incorporated by reference.

-   Hadlock, F. et. al., “Fetal Crown-Rump Length: Reevaluation of    Relation to Menstrual Age (5-18 weeks) with High-Resolution    Real-Time US,” Radiology, vol. 182, no. 2, pages 501-505, February    1992;-   Hadlock, F. et. al., “Estimating Fetal Age: Computer-Assisted    Analysis of Multiple Fetal Growth Parameters”, Radiology, vol 152,    no. 2, pages 497-501, August 1984.-   Chitty, L. et. al., “Charts of fetal size: 2. Head measurements”,    British Journal of Obstetrics and Gynecology, vol 101. pp 35-43,    January 1994.-   Chitty, et. al., “Charts of fetal size: 3. Abdominal measurements”,    British Journal of Obstetrics and Gynecology, vol. 101, pp. 1-7,    February 1994.-   Chitty, et. al., “Charts of fetal size: 4. Femur length”, British    Journal of Obstetrics and Gynecology, vol. 101, pp. 132-135,    February 1994.-   Hellman, L., et. al., “Growth and development of the human fetus    prior to the twentieth week of gestation”, Am. J. Obst. & Gynec.,    Volume 103, no. 6, pp. 789-800, Mar. 15, 1969.-   Goldstein, I., et. al., “Cerebellar measurements with    ultrasonography in the evaluation of fetal growth and development”,    Am. J. Obst & Gynec., Volumne 156, No. 5, pp 1065-1069, May 1987.-   Hata, T. and R. Deter, “A Review of Fetal Organ Measurements    Obtained with Ultrasound: Normal Growth”, J. Clin. Ultrasound    210:155-174, March/April 1992.-   Jeanty, P. et. al., “Estimation of Gestational Age from Measurements    of Fetal Long Bones”, Journal of Ultrasound in Medicine, Volume 3,    pp. 75-83, February 1984.

Biparietal Diameter (BPD)

The biparietal diameter is the transverse width of the head measuredbetween the two sides of the head. The biparietal diameter can be usedto calculate gestational age.

Head Circumference (HC)

The circumference of the fetus' head can be used to calculategestational age with a degree of accuracy that is slightly better thanthat derived from the biparietal diameter.

Abdominal Circumference (AC)

Abdominal circumference is measured at the widest point in the abdomen,through the liver at the level of the left portal vein or stomach.Abdominal circumference is determined not only by growing tissues(mainly liver) but also by nutrient storage such as subcutaneous fat andliver glycogen. Serial measurements of the abdominal circumference areuseful in monitoring the growth of the fetus.

Femur Length (FL)

The femur length measurement measures the longest bone in the body andreflects the longitudinal growth of the fetus. Its usefulness is similarto that of the biparietal diameter measurement. Accuracy of gestationalage from femur length measurements is relatively independent ofnutritional-growth retarding processes.

Crown Rump Length (CRL)

The crown rump length measurement can be made between 7 to 13 weeks andgives an accurate estimation of the gestational age. The crown rumplength measurement is an early standard of reference for fetal datingwith ultrasound and is useful in the first trimester of pregnancy

Estimated Fetal Weight (EFW)

Sonographic prediction algorithms use various combinations of abdominalcircumference (AC), femur length (FL), biparietal diameter (BPD), andhead circumference (HC), both singly and in combination, to make fetalweight estimations.

Intracranial Organs

Ratio of the Cerebellum's Lateral Ventricular Width to the HemisphericWidth (LVW/HW).

Cerebroatrial Distance (CAD).

Ratio of the cerebroatrial distance (CAD) to hemispheric width (HW).

Posterior Horn Width (PHW), measured from the medial wall to the lateralwall of the posterior horn of the lateral ventricle.

Cerebroposterior horn distance (CPHD), measured from the medial wall tothe lateral wall of the posterior horn of the lateral ventricle.

Transverse cerebellar diameter (TCD).

Heart

Left ventricular transverse diameter (LVTD).

Right ventricular transverse diameter (RVTD).

Aortic diameter (AOD).

Pulmonary artery diameter (PAD).

Lung

Left lung circumference (LLC).

Right lung circumference (RLC).

Lung Area (LA) in a transverse section of the fetal thorax containingthe four-chamber view of the heart.

Thymus

Maximal Anterior-posterior diameter (APD) of the thymus, measured in themidline at the sternum.

Liver

Liver Length (LL).

Spleen

Spleen Length (SL).

Spleen Width (SW).

Spleen Area (SA).

Pancreas

Length of fetal pancreas (FP-L).

Stomach

Longitudinal and anteroposterior diameters of the stomach.

Kidney

Anteroposterior Diameter.

Transverse Diameter.

Length.

Circumference.

Area.

Volume.

Adrenal Gland

Fetal adrenal gland area (FAGA).

Fetal adrenal gland length (FAGL).

Fetal adrenal gland circumference (FAGC).

Intestine

Colon diameter (CD).

Bladder

Maximum bladder volume (MBV).

Fetal urine production rate (FUPR).

Misc.

Anterior-posterior trunk/thorax diameter (APTD).

Transverse trunk diameter (TTD).

Spine length (SL).

As mentioned in the background section above, different dimensions offetal growth data are typically displayed as separate growth curves,with only one growth curve being displayed at a given time. Because thesonographer must page through a sequence of growth curves to obtain aglobal picture of the normalcy of the fetus' growth, the sonographer canoverlook an important growth curve. To remove this risk, this embodimentsimultaneously displays the plurality of generated fetal growth data ina graphical format (act 140). The plurality of fetal growth data is“simultaneously displayed” when all of the plurality of fetal growthdata is presented at a given time to a user for viewing, even if a delayprevents all of the fetal growth data from being initially displayedexactly at the same instant. The term “simultaneously display” isintended to distinguish from the sequential display of fetal growthdata, which occurs when a user pages through a sequence of individualfetal growth curves to cause the display of one fetal growth curve to bereplaced by the display of a different fetal growth curve. The pluralityof fetal growth data can be simultaneously displayed on a single displaydevice or across multiple display devices and can be presented in asingle graph or in multiple graphs. Further, while the phrase “graphicaldisplay format” is intended to distinguish from a mere listing ofnumerical data (e.g., a tabular chart of numerical values of fetalgrowth data), no limit is intended on the form of the graphical format.Additionally, it should be noted that the graphical display format caninclude elements in addition to the various dimensions of fetal growthdata, such as an image or a chart of numbers.

Turning again to the drawings, FIG. 3 is an example of a graphicaldisplay format of an embodiment that can be used to simultaneouslydisplay fetal growth data. In the embodiment shown in FIG. 3, sixdifferent dimensions of fetal growth data are simultaneously displayedin a graphical format on a single page. In this embodiment, eachdimension is represented by a bar on a graph, and abbreviations for eachdimension of fetal growth data appear along the bottom of the graph.Above each measurement name is a bar, normalized so that the midpoint ofthe bar represents the expected value (mean) of the physiologyrepresented by the fetal growth data, given the current estimate of thefetus' gestational age, which is 30 weeks, 4 days in this example. Theupper and lower extents of each bar are normalized to represent thestandard deviations expected in the measurement of the physiology for anormal fetus. Dots indicate measurements obtained during theexamination, and dots lying outside the normal range can be color-codedfor emphasis. If closer examination is required of a particulardimension (e.g., BPD), the bar representing that dimension can beselected using a user interface device and expanded into a traditionalgrowth curve plot.

In contrast to conventional display techniques in which each dimensionof fetal growth data is displayed on its own graph separate from allother anatomical data, the display format of this embodiment provides animproved mechanism for rapid determination of the normalcy of thecurrent fetal state by simultaneously displaying several components offetal growth data. In this embodiment, values and standard deviations ofseveral anatomic measurements made during an examination are graphicallydisplayed side-by-side so that multiple dimensions of fetal growth datacan be quickly evaluated by a physician or sonographer. Because thisdisplay format simultaneously displays multiple dimensions of fetalgrowth data, a physician or sonographer can establish whether the fetusis developing normally in a single glance. Providing a multidimensionalview of fetal growth data can significantly decrease the likelihood thatan important aspect of the fetal physiology will be overlooked and,thus, reduce the possibility of an inaccurate diagnosis or amisdiagnosis of fetal pathology. By allowing all aspects of fetaldevelopment to be easily assessed by examination of a single graph thatpresents all of the fetal growth data in an easy-to-read format, themultidimensional display format of this embodiment overcomes thedisadvantages of existing growth curve presentation techniques byproviding a superior perspective on all dimensions of fetal growth.

It should be noted that different graphical display formats can be usedto simultaneously display fetal growth data. For example, as shown inFIG. 4, the graphical format of FIG. 3 can be modified to allow therepresentation of fetal growth trends during the gestation by includingdata from multiple examinations throughout the gestation. In thegraphical display format shown in FIG. 4, each dimension of fetal growthdata contains a set of points representing data acquired throughoutpregnancy, with the right-most point in each bar representing the datacollected at the noted gestational age (30 weeks, 4 days).

FIG. 5 shows an alternate presentation of multidimensional fetal growthdata that includes results from multiple examinations throughoutgestation. In the graphical display format of FIG. 5, biparietaldiameter, head circumference, and abdominal circumference are allplotted on the same graph. This graph illustrates expected value (mean)and standard deviations for each of the dimensions of fetal growth dataversus gestational age. The “dots” (squares, triangles, and circles) onthe graph indicate measurements obtained during the examination atvarious gestational ages, and each of the dimensions of fetal growthdata is normalized with respect to the mean.

In the graphical display formats described above, multiple dimensions offetal growth data were plotted on the same graph (i.e., different fetalgrowth data were overlapped onto the same display area). In an alternategraphical display format (shown in FIG. 6), multiple dimensions of fetalgrowth data are plotted on separate graphs (i.e., on separate displayareas), while still being simultaneously displayed on a single displaydevice 600. The various dimensions of fetal growth data can benormalized with respect to one another in this graphical display format.

In the embodiments described above, the fetal growth data wassimultaneously displayed on the ultrasound system that created the imagefrom which the fetal growth data was generated. In an alternateembodiment, the fetal growth data is simultaneously displayed on animage review system instead of on the ultrasound system that created theimage from which the fetal growth data was generated. As used herein,the term “image review system” refers to any device other than theultrasound system that created the image from which fetal growth datawas generated that is capable of simultaneously displaying a pluralityof fetal growth data. An image review system can be, for example, ageneral-purpose or specialized computer, a personal digital assistant(PDA), or another ultrasound system. The fetal growth data can beprovided from an ultrasound system to the image review system viaremovable media (e.g., a magneto-optical disk), a network (e.g., a localarea network in a hospital or the Internet), a wireless transmission, orany other suitable technique. In addition to simultaneously displayingfetal growth data, the image review system can perform other functions,such as displaying images, making measurements of anatomical structuresshown in the images, generating fetal growth data based on themeasurements, and creating medical reports.

Instead of simultaneously displaying fetal growth data, theseembodiments can be used to simultaneously display non-obstetrics-baseddata (e.g., cardiology data). Data other than that generated frommeasurements taken of anatomy shown in a medical image can also besimultaneously displayed. The following is an example using timeintensity curves.

Example Using Time Intensity Curves (TIC)

Another application of the general technique described above relates totime intensity curves (TIC) for cardiac contrast. TIC curves provide away of determining how well heart tissue is functioning. In operation, acontrast agent is injected into the body. When the contrast agent hassaturated the myocardium of the heart, for example, the ultrasound imageof the myocardium appears very bright. At this time, a powerfulultrasonic pulse bursts the bubbles of which the contrast agent iscomprised, causing the myocardium to appear dark. Now, as the heartcontinues to pump, contrast agent gradually fills the myocardium again.The speed with which this occurs can be plotted, producing atime-intensity curve. An individual TIC curve shows increasing intensityas a function of time. The rapidity with which the contrast agentrefills the chamber is a measure of cardiac pathology (slow refill rateimplies unhealthy heart muscle). Similar quantification of blood flowcan also be done in the kidney or other perfused organs.

Several mathematical models for a TIC curve are available. Onemathematical model for a TIC curve is:

A(1−ê(−bt))+C

-   -   where:        -   A, b, and C are constants        -   t is time        -   e is 2.7182818 . . . .        -   ̂ is exponentiation

Another commonly-used function is A*t*ê(−alpha*t)+C. Both functions arediscussed in Wei et al, “Basis for Detection of Stenosis Using VenousAdministration of Microbubbles during Myocardial ContrastEchocardiography: Bolus or Continuous Infusion,” Am Coll Cardiol32:252-60 (1998), which is hereby incorporated by reference. There arealso measured parameters such as arrival time, time to peak, half-timeof wash-in, and half-time of wash-out that can be used to describe thetime-intensity curve.

The mathematical model “A(1−ê(−bt))+C” is an idealization expressingasymptotic increase of intensity from a minimum of C to a maximum ofA+C. Given a TIC curve based on real ultrasound data, one can fit theabove mathematical model, estimating the best-fit values for A, b, andC. A, b and the product A*b have physiological meaning and have beenproposed as diagnostic of disease. See Linka et al., “Assessment ofTransmural Distribution of Myocardial Perfusion with ContrastEchocardiography,” Circulation 98:1912-1920 (1998), which is herebyincorporated by reference. The following discussion of displaying bvalues can equally be applied to the other parameters or theircombination. The parameter “b,” which is a measure of the rapidity ofcontrast agent refilling the chamber, has an average value to be foundamong a population of healthy hearts, and a standard deviation aboutthat average value which might be found in a large population of healthyhearts. But, an unhealthy heart might display a value of b which differsfrom normal by, say, 2.5 standard deviations.

Some conventional ultrasound machines are able to produce and displaymultiple TIC curves corresponding to different locations of the heartwall. However, with this embodiment, rather than displaying the rawcurves together, the above equation would be fitted to each of theindividual curves, obtaining for each a value of “b.” Then, thenormalized b's are displayed on a single plot. Thus, thesonographer/physician sees, at a glance, not several curves overlyingeach other but rather a set of “b” values expressed in terms of how manystandard deviations “b” is from normal. Not only is this much “cleaner”to the eye (a less busy plot), but it may also help indicate pathologymore easily. In the case where one or two curves are particularly slow,then it may be easy to detect pathology using the traditional plottingmethod, because the slow curves stand out from the crowd. But if theyare all slow, pathology may not be as obvious. However, the display ofnormalized “b's” will make the pathology obvious, because all thenormalized “b's” will lie away from the “Normal” value.

Furthermore, it may be possible to develop theoretical models for theexpected “b” for different parts of the heart muscle. In this case, eachTIC measurement at a different location would be normalized using theexpected “b” appropriate for that location, and again, the gamut ofmeasurements would be simultaneously displayed in a single graphicaldisplay to determine which parts of the heart are diseased. Comparisonof the multi-site TIC curves without such normalization could besignificantly more difficult to properly interpret.

In another embodiment, a time intensity curve is plotted on a graphsimilar to that shown in FIG. 7. Specifically, a single graph displaysan ultrasound contrast time intensity curve of a study along with threecurves. The first curve represents an expected ultrasound contrast timeintensity curve, and the second and third curves represent a statisticalvariation of the expected ultrasound contrast time intensity curve.

CONCLUSION

While the embodiments have been described above in terms of ultrasoundimages, it should be noted that these embodiments can be used with anytype of medical image. Examples of different types of medical imagesthat can be used with these embodiments include, but are not limited to,images created with any of the following imaging modalities: computedtomography (CT), magnetic resonance imaging (MRI), computed radiography,magnetic resonance, angioscopy, color flow Doppler, cystoscopy,diaphanography, echocardiography, fluoresosin angiography, laparoscopy,magnetic resonance angiography, positron emission tomography,single-photon emission computed tomography, x-ray angiography, computedtomography, nuclear medicine, biomagnetic imaging, culposcopy, duplexDoppler, digital microscopy, endoscopy, fundoscopy, laser surface scan,magnetic resonance spectroscopy, radiographic imaging, thermography, andradio fluroscopy.

It is intended that the foregoing detailed description be understood asan illustration of selected forms that the invention can take and not asa definition of the invention. It is only the following claims,including all equivalents, that are intended to define the scope of thisinvention.

1-42. (canceled)
 43. A method for displaying an ultrasound contrast timeintensity curve, the method comprising: (a) displaying a first curverepresenting an expected ultrasound contrast time intensity curve; (b)displaying second and third curves above and below the first curve,respectively, the second and third curves representing a statisticalvariation of the expected ultrasound contrast time intensity curve; and(c) displaying an ultrasound contrast time intensity curve of a study;wherein the ultrasound contrast time intensity curve and the first,second, and third curves are displayed on a single graph.
 44. The methodof claim 43 further comprising generating the ultrasound contrast timeintensity curve.
 45. The method of claim 43 further comprising:injecting a contrast agent into a body; applying an ultrasonic pulse toburst bubbles of which the contrast agent is comprised; imaging a regionin the body before and after the application of the ultrasonic pulse;and determining a speed at which contrast agent fills the region. 46.The method of claim 43 wherein the study comprises a cardiac contraststudy.
 47. The method of claim 43 wherein the ultrasound contrast timeintensity curve represents intensity as a function of time of contrastagents.
 48. The method of claim 43 further comprising: measuring arrivaltime as a function of the ultrasound contrast time intensity curve. 49.The method of claim 43 further comprising: measuring time to peak as afunction of the ultrasound contrast time intensity curve.
 50. The methodof claim 43 further comprising: measuring half-time of wash-in as afunction of the ultrasound contrast time intensity curve.
 51. The methodof claim 43 further comprising: measuring half-time of wash-out as afunction of the ultrasound contrast time intensity curve.
 52. The methodof claim 43 wherein the ultrasound contrast time intensity curve isderived from raw imaging data.
 53. The method of claim 43 wherein thestatistical variation comprises deviation from a normal represented bythe first curve.
 54. The method of claim 43 wherein (a), (b), and (c)are performed on a medical diagnostic imaging system.
 55. The method ofclaim 43 wherein (a), (b), and (c) are performed on an image reviewsystem.
 56. The method of claim 43 wherein the ultrasound contrast timeintensity curve is displayed in response to user selection of one of aplurality of simultaneously displayed normalized measurements.